I was still "raw" in experience when I suddenly read that php 7 was out and when some article mentioned there is a slight modification in the syntax of php 7, I got put-off from learning php 5 from any tutorial and deliberately tried forgetting what I learn so far from tizag (which doesn't even mention what version they're teaching, like most tutorials forget to mention that) and waited nearly 1.5yrs for a beginner level tutorial to come-out that would teach me php 7 from ground-up but no such tutorial has come-out even today as most php 7 tutorials don't teach you from the beginning of the language but only teach you what is different in php 7 compared to php 5.

Anyway, since, programmers everywhere keep telling me it;s the same language and not to wait for php 7 tutorial to come-out that would teach from the beginning and since they have assured me the syntax is still the same in php 7 like it was in php 5 and earlier versions then I have no choice but to revise again after 1.5yrs of my long waiting break.

This time, however, going slowly in the "re-learning" so to get a solid understanding of thto not overlook any aspect of it. Won't run this time. Saying all this, I do have a little experience in the language by watching youtube tutorials and fiddling with their codes modifying them according to my needs and asking for help in the forums.

When I learnt from tizag, I can't remember them teaching anything about expressions or tokens (unless I've forgotten it over 1.5yrs) but going through tutorialspoint.com I came across it. Hence, the questions:

Q1a. In php, what is the difference between a statement and an expression ?

I know statements must end with a semi colon but what really is an expression and what really is a token ? I didnt really understand this explanation: